Historically, Industrial Control Systems (ICS) could exist as a closed-loop, with an air-gapped network and a solid physical security program insulating them from the outside world. An operator could trust the integrity of their operations based on process outputs, and when processes broke down maintenance was brought in to locate and fix the issue.
Improve Legacy Critical Infrastructure Protection with Automated Monitoring and Anomaly Detection for DNP3
DNP3 – Distributed Network Protocol 3.0 – is the second most-widely used serial communications protocol in Industrial Control Systems (ICS), after Modbus. As EPRI (Electric Power Research Institute) mentioned in a 2019 technical update: “it is the most widely used utility communications protocol in North America”